structure
Septum
- partition/ wall that separates inside of nose
- two cavities
Chilia (respiratory mucosa)
- Beat in one direction
- move mucus (dust & pollen) upward for removal
- line the upper structures
External Respiration
- Pulmonary ventilation
- Breathing
- Exchange of gases in the lungs
- Pulmonary gas exchange
Inspiration
- active movement of air into lungs
- inspiratory muscles
~ diaphragm
-> flattens & increases length of thorax
-> largest & most important respiratory muscle
~ intercostals
-> contract & elevate the ribs
-> increase the size of the thorax
— front to back & side to side
- pressure reduction (vacuum)
~ air enters the lungs
Pulmonary volumes
~ average 500 mL
~ normal quiet breathing
(Inspiration and expiration)
~ volume of air exhaled after a normal inspiration
Nose
- sinuses drain into the nose
Lobes of lungs # on L + R
3 on the right
2 on the left
External Respiration (cont)
Gas Exchange and transport
- Carbon dioxide
~ moves out of capillary blood in the lungs
~ moves into alveolar air
~ moves out of body in expired air
- Oxygen
~ moves from alveoli into lung capillaries
~ hemoglobin combines with oxygen
Expiration = exhaling
- movement of air out of lungs
~ quiet expiration = passive process
~ thorax returns to resting size and shape
-> becomes smaller
~ increased pressure forces out air
Pulmonary Volumes 2
- Expiratory reserve volume (ERV)
~ amount of air that can be forcibly exhaled
~ after exhaling the tidal volume
- inspiratory reserve volume (IRV)
~ amount of air that can be forcibly inspired
~ over and above the normal inspiration
- lined with mucous membranes ( aka mucosa)
- nasopharynx
~ 2 nasal cavities
~ opening of auditory (Eustachian) tubes
~ Adenoids
- Oropharynx
~ opening to mouth
~ tonsils
- Laryngopharynx
~ above the larynx
Lungs
- Size- Fills the chest cavity
~ except for middle space
~ heart and large blood vessels
- apex
~ narrow upper part of each lung
~ under collarbone
- Base
~ Broad lower part of each lung
~ rests on diaphragm
- Pleura :
~ moist, smooth, slippery
~ 2 layers
~ membrane that lines chest cavity (parietal pleura)
~ covers outer surface of lungs (visceral pleura)
Internal respiration
- systemic gas exchange
- cellular Respiration
- Exchanges of gases in the tissues
forceful expiration
uses muscles
~ speak, sing, exercise
~ intercostals
-> moves ribs
-> make thorax smaller
— from side to side / front to back
~ abdominal muscles
-> elevate the diaphragm
-> make thorax smaller
— from top to bottom
Pulmonary Volumes 3
Vital Capacity
- Largest amount of air in one deep breath
- Deep inhalation & full exhalation
- Tidal Volume + ERV + IRV
- Lined with mucous membranes
- cartillegal framework
~ thyroid cartilage = Adam’s apple
~ largest of the laryngeal cartilage
- Epiglottis partially covers opening to larynx
- vocal cords stretch across larynx
Bronchial tree
- two main branches off of the trachea
~ right and left primary (main) bronchi
- bronchi branch into smaller and smaller tubes
~ bronchioles
- bronchioles end in alveolar sacs
~ clusters
~ microscopic
~ walls of alveolar sacs are made up of alveoli
Internal respiration (cont)
Systemic gas exchange
- oxygen
~ moves out of capillary blood in the tissues
~ moves into tissues cells
- carbon dioxide
~ moves from tissue cells
~ into capillary blood of the tissues
~ hemoglobin combines with carbon dioxide, too
- blood transports these gases
Overall Structure
Upside-down tree
- hollow trunk = Trachea
- Branches of the tree = Bronchial Tubes
- Leaves of the tree = Alveoli
Regulation of Ventilation
- Homeostasis of blood gases
- Body adjust to varying demands
~ both oxygen supply & carbon dioxide removal
- Brainstem
~ central regulatory centers
~ respiratory control centers
~ inspiratory and expiratory centers
~ normal rate and depth of respirations
~ 12-20 breaths / minute
Trachea
- tube = windpipe
- extends from larynx into the thoracic cavity
- mucous lining
- C-shaped rings of cartilage
~ Hold trachea open
Bronchial Tree
(from largest to smallest)
- Trachea
- Right and left primary bronchi
~ Right is more easily obstructed
- Secondary bronchi
- bronchioles
- alveolar ducts
- alveoli
This is a lot BUTTTTT
Keep going… you got this!!
<3 future nurse <3
Overall structure
-> Alveoli
- Microscopics sacs
- enclosed by capillaries
~ passive transport
~ diffusion
~ exchange of gases
-> oxygen & carbon dioxide
-> O2 & CO2
Regulation of Ventilation
- Cerebral cortex
~ limited , voluntary control of respiration
- respiratory reflexes
~ Chemoreceptors : respond to changes
-> carbon dioxide
-> oxygen
-> blood acid levels
- pulmonary stretch reflexes
-> respond to the stretch in lungs